/**
 * Copyright &copy; 2018 <a href="https://gitee.com/hackempire/patch-generator-parent">emsite</a> All rights reserved.
 */
package com.empire.patch.generator.utils;

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.zip.ZipEntry;
import java.util.zip.ZipInputStream;
import java.util.zip.ZipOutputStream;

/**
 * 类ZipUtil.java的实现描述：zip 工具类
 * 
 * @author arron 2018年4月12日 下午7:06:06
 */
public final class ZipUtil {
    private ZipUtil() {
        // empty
    }

    /**
     * 压缩文件
     * 
     * @param filePath 待压缩的文件路径
     * @return 压缩后的文件
     */
    public static File zip(String filePath) {
        File target = null;
        File source = new File(filePath);
        if (source.exists()) {
            // 压缩文件名=源文件名.zip
            String zipName = source.getName() + ".zip";
            target = new File(source.getParent(), zipName);
            if (target.exists()) {
                // 删除旧的文件
                target.delete();
            }
            FileOutputStream fos = null;
            ZipOutputStream zos = null;
            try {
                fos = new FileOutputStream(target);
                zos = new ZipOutputStream(new BufferedOutputStream(fos));
                addEntry("/", source, zos);
            } catch (IOException e) {
                throw new RuntimeException(e);
            } finally {
                IoUtil.closeQuietly(zos, fos);
            }
        }
        return target;
    }

    /**
     * 扫描添加文件Entry
     * 
     * @param base 基路径
     * @param source 源文件
     * @param zos Zip文件输出流
     * @throws IOException
     */
    private static void addEntry(String base, File source, ZipOutputStream zos) throws IOException {
        // 按目录分级，形如：/aaa/bbb.txt
        if ("/".equals(base)) {
            //修复打包压缩文件中文件名出线“/”开头的文件名
            base = "";
        }
        String entry = base + source.getName();
        if (source.isDirectory()) {
            for (File file : source.listFiles()) {
                // 递归列出目录下的所有文件，添加文件Entry
                addEntry(entry + "/", file, zos);
            }
        } else {
            FileInputStream fis = null;
            BufferedInputStream bis = null;
            try {
                byte[] buffer = new byte[10240];
                fis = new FileInputStream(source);
                bis = new BufferedInputStream(fis, buffer.length);
                int read = 0;
                zos.putNextEntry(new ZipEntry(entry));
                while ((read = bis.read(buffer, 0, buffer.length)) != -1) {
                    zos.write(buffer, 0, read);
                }
                zos.closeEntry();
            } finally {
                IoUtil.closeQuietly(bis, fis);
            }
        }
    }

    /**
     * 解压文件
     * 
     * @param filePath 压缩文件路径
     */
    public static void unzip(String filePath) {
        File source = new File(filePath);
        if (source.exists()) {
            ZipInputStream zis = null;
            BufferedOutputStream bos = null;
            try {
                zis = new ZipInputStream(new FileInputStream(source));
                ZipEntry entry = null;
                while ((entry = zis.getNextEntry()) != null && !entry.isDirectory()) {
                    File target = new File(source.getParent(), entry.getName());
                    if (!target.getParentFile().exists()) {
                        // 创建文件父目录
                        target.getParentFile().mkdirs();
                    }
                    // 写入文件
                    bos = new BufferedOutputStream(new FileOutputStream(target));
                    int read = 0;
                    byte[] buffer = new byte[10240];
                    while ((read = zis.read(buffer, 0, buffer.length)) != -1) {
                        bos.write(buffer, 0, read);
                    }
                    bos.flush();
                }
                zis.closeEntry();
            } catch (IOException e) {
                throw new RuntimeException(e);
            } finally {
                IoUtil.closeQuietly(zis, bos);
            }
        }
    }
}
